A Lesson in Subtraction

 A Lesson in Subtraction, by Burst

**castration**

Math was never my best subject. Even the simple stuff in elementary school gave me trouble so by 9th grade Algebra I was pretty much lost. Concentrating was hard, made even more difficult by my teacher, Mrs. Klein. She was the most beautiful woman I'd ever seen. 5'7", 120 lbs, long black hair, well tanned skin, toned body, and always wore silky blouses, short skirts, and high heels. She was absolutely...

"Are you paying attention?"

"What?"

"I asked you which numbers in this set are prime."

"Umm... 2, 4, 6..."

"Could you stay a few minutes after class?"

When the bell rang, I approached Mrs. Klein at her desk. She got right to the point.

"I've noticed you've been having difficulty in class lately. You've failed the last three tests, which puts you in danger of failing for the semester."

"I know, but it's just so hard. I don't understand..."

"It's ok," said Mrs. Klein. "I want to help. Perhaps some after school tutoring?"

"Okay."

"Wonderful. Be at my home at 4:00 this afternoon. 431 Burdeshaw St." Her home? Wow.

That afternoon, I flew over there, arriving at 3:40. I rang the bell several times, before Mrs. Klein finally answered. She was wet, wearing only a silky white robe that barely reached the top of her knees.

"You're early," she said.

"I'm sorry. Just eager to learn, I guess."

"That's ok," she said. "Come on in." I walked in and sat down on the couch.

"Can I get you something to drink?" she asked. "A Coke?"

"Sure."

Mrs. Klein walked into the kitchen, returning moments later with Coke in hand. She held it out for me to take, but before I could grab it, the glass slipped from her hand, landing in my lap and splattering Coke everywhere.

"OH!" she exclaimed. "I am so sorry!" Mrs. Klein ran to the kitchen, grabbed some paper towels, and began wiping at my crotch with them, causing an instant and full erection.

"Your pants and shirt are soaked," she said. "I'm so sorry. I'll wash them for you. Let me have them."

"Just... take them off?" I asked nervously.

"I'll find something for you to put on," she said. "But yes, go ahead and get them off." I slowly took off my shirt and then my pants. Her eyes instantly locked on my crotch, making me blush, but also causing my hard-on to throb even more.

"Your underwear are soaked," she said. "I'd better wash them too. Take them off in the bathroom, while I find something for you to put on." I went to the bathroom and slipped off my underwear. A minute later, Mrs. Klein came to the door. I opened it a crack, and she tossed in a light blue very-worn barely knee-length bathrobe.

"Sorry, that's all I have," she said. "There haven't been any men's clothes in this house since my husband left last year... and I think you might be a little too masculine for one of my skirts. Hee, hee." I walked out and nervously handed her my wet underwear. She took them to the laundry room as I returned to the living room and sat down on the couch. Almost immediately, the robe fell open and my penis was exposed. I quickly put it back in and retied the belt. Seconds later, Mrs. Klein returned and sat down next to me on the couch.

"Well, let's get started," she said. "We can go over some basics first, then work some problems. Just read along with me for now." Mrs. Klein placed the Algebra book in her lap and opened it. As she read aloud, I stared at the pages... for a couple of seconds, then my eyes wandered down her beautiful tan legs. They were so firm and tone, I knew she must work out...

"So do you understand all that?"

"I'm... not sure."

"That's ok," she said. "Maybe reading it isn't the best way for you to learn. But I'll find something that motivates you. Let's set the book aside for a second." Mrs. Klein slid the book off her lap to the side, which caused her robe to fall open, exposing her bush. I couldn't help but to stare in awe and suddenly, my erection burst forth from my robe. Mrs. Klein gasped and covered herself, as I looked away, my face a burning red.

"I see what motivates you now," she said.

"I'm... so sorry," I said, almost hysterically. "I... I..."

"It's ok," she said. "Maybe we can use this... as long as it remains our little secret. Promise?"

"Yes ma'am," I said. Mrs. Klein slipped her hand into my robe and began fondling my penis and testicles.

"Like that?" she asked.

"Yes ma'am," I said, blushing again.

"Well, you'll get more," she said, removing her hand. "When you learn Algebra. Now let's get started." Mrs. Klein showed me how to work a few more problems, then asked me to work one on my own.

"That's correct," she said, as I finished my problem. Mrs. Klein lowered her head, and wrapped her lips around my penis, sucking it for just a few seconds before coming back up.

"Now let's work another," she said. I did the next problem.

"I'm sorry," she said. "That's not it." Mrs. Klein reached into my robe again, grabbed my balls, and began squeezing.

"AAAGGGHH!"

"That's what you get when you miss one," she said, releasing my nuts. "I think it's quite a motivator. Let's try another." I worked another problem, and once again I was wrong. This time, she slapped my sack, causing me to double over in pain.

"You'd better start picking this up faster," she said. "That is, if you ever want to have children." I worked another problem. This time, I was correct. She pulled open her robe, exposing her breasts, and allowed me to suck them for a moment.

This is how it went for the next couple of weeks. Every afternoon, I'd come over and we'd work problems for about an hour. When I was wrong, she kicked, slapped, squeezed, and otherwise tortured my genitals. But when I was right, I was given handjobs, blowjobs, and allowed to pleasure her in many ways, although never with intercourse.

Finally, test time came. I did my work with confidence then took the paper to her desk.

"Come over after school," she whispered softly. "And I'll grade it."

That afternoon, I went to Mrs. Klein's house. As was the routine now, I went in, removed my clothes, put on my robe, and joined her in the living room. She was sitting on the couch, wearing only her robe and holding my paper. Next to her was a device I'd never seen before. Some kind of large vice-grips.

"Time for the moment of truth," she said. "Take off your robe." I slipped off the robe and walked over to Mrs. Klein. She guided me to the vice grips, and slipped my testicles inside.

"What are you doing?!" I asked.

"As you know, if you miss 20 questions on this test, you fail," she said. "So I've calibrated these vice grips mathematically, so on the 20th turn, the pressure will be enough to rupture your testicles."

"WHAT?!" I screamed. "NO!"

"Don't think you'll pass?" she asked. "If you're not confident, I'll release you... but then, you won't get your reward if you pass."

"Reward?" I asked.

"Oh yes," she said, seductively. "Hot sweaty sex, pure and simple. Your throbbing cock thrusting in and out of my wet hot pussy... till you fill me with your sweet young cum. Would you like that?"

"Yes ma'am," I said, now fully erect, despite my balls being in the vice.

"Good," she said. "Let's begin." Mrs. Klein began grading my paper. The first problem I missed was #7. As she marked it in red, she gave the wheel on the vice grips a turn, causing an increase in pressure to my balls. It didn't really hurt... yet. By the tenth twist, I was standing there in agony.

"You're not doing as well as I thought," she sighed. "You know who you remind me of?"

"Who?" I asked, whimpering.

"Oops... missed two more," she said. She gave the wheel two more twists.

"AGGGHH!" I groaned.

"As I was saying, you remind me of my ex-husband." She gave the wheel another twist.

"He was always a dense one..." She twisted it again.

"He never listened to me. No matter how many times I explained something, he just didn't get it." Mrs. Klein twisted the wheel two more times.

"Nope, he never cared what I had to say. To him, I was just a hot body..." Mrs. Klein twisted the wheel for the 17th time.

"He didn't care that I had an IQ of nearly 180, or that I had a master's degree... oh no. All he cared about was sex!"

"Mrs. Klein," I groaned. "Please... UUUGHH! Stop!"

"That's the only way I could communicate with him," she said, twisting the wheel again. "I wanted to castrate him, just to see if it made him any smarter." She turned the wheel for the 19th time, and I squealed in agony. My balls were practically flat, and I could tell they were ready to pop.

"It'll be interesting to see if you make better grades after I bust your fucking nuts" she growled. "I... hmmm... seems you only missed 19."

"Thank God," I groaned.

"Oh wait," she said with a sadistic smile. "You forgot to show your work on #39. That's means you lose another two... and I'm not just talking about points!" Mrs. Klein had an evil gleeful look on her face as she gave the wheel a final twist.

"AAAAAAAAAAAAAAAAAAGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!" I screamed as my testicles popped.

Mrs. Klein released me from the grips and I fell to the floor, where I lay writhing in agony. She laughed triumphantly and began kicking at what was left of my manhood.